Al掺杂LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2)材料结构改性及电化学性能研究  

Structural Modification and Electrochemical Performance of Al-doped LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2) Materials

作　　者：邢建祥 杨延朴 杨集舜 徐越 杨廷海[1] 杨刚 XING Jianxiang;YANG Yanpu;YANG Jishun;XU Yue;YANG Tinghai;YANG Gang(Jiangsu Laboratory of Precious Metals Processing Technology and Application,School of Chemistry and Chemical Engineering,Jiangsu University of Technology,Changzhou 213000,Jiangsu,China;Jiangsu Key Laboratory of Advanced Functional Materials,School of Materials Engineering,Changshu Institute of Technology,Changshu 215500,Jiangsu,China)

机构地区：[1]江苏理工学院化学化工学院江苏省贵金属深加工技术及应用重点建设实验室,江苏常州213000 [2]常熟理工学院材料工程学院江苏省先进功能材料重点实验室,江苏常熟215500

出　　处：《材料导报》2025年第1期122-126,共5页Materials Reports

基　　金：国家自然科学基金(51802030);江苏省高等学校自然科学研究项目(23KJA430007)。

摘　　要：三元正极材料LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2)(NCM523)由于其适中的价格和高能量密度而广受关注,但低循环稳定性使其商业化应用受限。本研究以Al为掺杂元素,采用共沉淀结合高温固相的方法制备不同数量的Al原子取代Mn位的三元NCM523微米颗粒型正极材料。结果表明,适量的Al掺杂可以增强过渡金属层的稳定性,显著改善NCM523材料循环稳定性差的问题。Al掺杂量满足Al/Li物质的量比为7%时获得了最佳的电化学性能,在2.7~4.5 V、0.1C倍率下首次放电比容量为165.7 mAh·g^(-1),经50次循环后衰减为134.3 mAh·g^(-1),容量保持率为81.05%。高温(55℃)环境下,Al/Li物质的量比为7%的样品依然保持最佳的电化学性能。The temary cathode material LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2)(NCM523)has attracted much attention due to its moderate price and high energy density.Nevertheless,the low cyclic stability of NCM523 has hindered its commercial application.In this work,a series of modified NCM523 cathode materials in which various amounts of Al atoms substituted for Mn atoms were prepared by a hybridized method combining co-precipitation and high-temperature sintering.The results showed that the appropriate dosage of Al could enhance the stability of the transition metal layer and sig-nificantly improve the poor cyclic stability of NCM523 material.The best electrochemical performance was obtained when an Al dosage of 7% molar ratio(Al to Li)was adopted,as it provided a discharge specific capacity of 165.7 mAh.g^(-1) within the voltage range of 2.7-4.5V at 0.1C current density,which deteriorated to 134.3 mAh·g^(-1) after 50 cycles,with 81.05% capacity retention.At the high-temperature(55℃)condi-tion,the sample with 7%AI/Li molar ratio still maintained the best electrochemical perfomance.

关 键 词：锂离子电池 LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2) AL掺杂 循环稳定性 

分 类 号：TQ174[化学工程—陶瓷工业]